A Tax Break Now, a Bill Later — and When That’s the Smart Trade

Wanda Kessler, 51, an HR director in Portland, Oregon, found out she’d been making nondeductible Traditional IRA contributions for six years only when she sat down to actually withdraw the money. Her income and workplace 401(k) had phased out the deduction years ago, so a portion of every contribution since then was already-taxed money — money the IRS has no record of unless she’d filed a specific form every single year. She hadn’t. Her accountant’s blunt assessment: without that paper trail, the IRS would tax the same dollars twice, once when she earned them and again when she withdrew them, and there was no way to prove otherwise after the fact.

For 2026, the contribution limit is $7,500 a year (or $8,600 if you’re 50 or older). The deduction may phase out if you (or your spouse) have a workplace retirement plan and your income is above certain thresholds — but you can still contribute even without the deduction, just with different tax treatment on withdrawal.

Example: $500 a month for 30 years at 7% grows to roughly $610,000. None of that growth is taxed along the way — dividends and gains inside the account aren’t touched by the IRS year to year — but when you eventually withdraw, whatever total it reaches, a slice of it is the IRS’s money, taxed as ordinary income.

The form that’s the only proof you already paid tax on it

When Wanda’s deduction phased out, her contributions didn’t stop being allowed — they just stopped being pre-tax. The IRS requires anyone making a nondeductible contribution to a Traditional IRA to file Form 8606 for that tax year, which records the after-tax “basis” in the account. That basis is what prevents double taxation: at withdrawal, the nondeductible portion comes out tax-free, and only the growth and any deducted portion is taxed. Skip filing Form 8606 in the years it applied, and there’s no IRS record that any of the money was already taxed — the account looks, on paper, exactly like one made entirely of pre-tax contributions. Wanda’s six years of undocumented nondeductible contributions put roughly $19,000 of already-taxed principal at risk of being taxed again on withdrawal, purely because a form that takes ten minutes was never filed.

The core trade-off versus a Roth: you get the tax break now instead of later. That’s the better deal if you’re in a high tax bracket today and expect a lower one in retirement — common for people in their peak earning years. But that trade-off only holds if the paperwork matches the reality. A missed Form 8606 doesn’t just risk a penalty for the missing form itself — it risks losing the entire tax benefit of having contributed after-tax money in the first place.

One rule to know: Required Minimum Distributions (RMDs) force you to start withdrawing a minimum amount once you reach a certain age, whether you need the income or not — unlike a Roth, which has no lifetime RMDs. That makes a Traditional IRA slightly less flexible for anyone hoping to leave the account untouched for heirs, and it makes an accurate basis record even more important, since RMD calculations also depend on knowing which part of the account was already taxed.

The rollover hustle, and the rule meant to catch it

The traditional IRA’s pitch is the upfront deduction, but the fine print removes it for exactly the people most pitched: covered by a workplace plan and above modest income limits, your contribution may be wholly nondeductible — and nobody at the sales desk checks before congratulating you. The larger hustle happens at job changes: “rollover specialists” migrating 401(k) balances into IRAs invested in proprietary funds or annuities with advisory wraps. The Department of Labor’s Prohibited Transaction Exemption 2020-02 specifically requires financial professionals recommending a rollover to document why it’s in the client’s best interest, including comparing the fees and services in the old plan against the new one — a rule that exists precisely because a rollover recommended by whoever calls first, into a 1%-plus product, is often a commission wearing advice’s clothing.

Run your own numbers, right here

YOU ENTER your monthly contribution, expected return, and years invested. IT TELLS YOU the ending balance — the number that only stays fully yours if the basis on any nondeductible portion was actually filed and tracked, year after year, the way Wanda’s wasn’t.

Frequently asked questions

Deductible for me or not?

Depends on workplace-plan coverage and MAGI — check the IRS limits for your year before assuming. If nondeductible, weigh the backdoor Roth route instead; deductions that don’t exist shouldn’t drive contributions.

My advisor says annuities inside my IRA add “guarantees” — is that worth it?

An IRA is already tax-deferred; an annuity inside it stacks cost on redundancy. The “guarantee” is an insurance product’s fee schedule wearing retirement vocabulary.

What do I do if I never filed Form 8606 in years I should have?

The IRS generally allows filing a late or amended Form 8606 to establish basis after the fact, though it can require reconstructing years of contribution records and, in practice, working with a tax professional to document the basis credibly. It’s a fixable problem the earlier it’s caught — the risk grows the longer it goes unaddressed and the more the account has grown in the meantime.

How do I know if this applies to me?

Check your tax returns for any year you contributed to a Traditional IRA while also covered by a workplace plan with income above the deduction phase-out for your filing status. If a Form 8606 isn’t attached to that year’s return, the nondeductible portion of that contribution has no basis on file with the IRS, and it’s worth addressing before it compounds into more years of the same gap.

None of this means a Traditional IRA is a bad choice — for someone in Wanda’s bracket during her peak earning years, the tax-deferred growth is genuinely valuable. What it means is that the account has two separate jobs: growing the money, and keeping an honest paper trail of which dollars were already taxed. The growth takes care of itself. The paper trail doesn’t, and it’s the one part of “set it and forget it” retirement advice that specifically cannot be set and forgotten — it needs a fresh Form 8606 every single year a nondeductible contribution is made, not just the first year. Wanda’s fix took an afternoon with her accountant reconstructing six years of contribution records from old statements — tedious, but far cheaper than paying tax twice on the same $19,000 would have been, and cheaper still than finding out at 73 when RMDs start and there’s no one left who remembers the details.

Sources: IRS Form 8606 instructions, nondeductible IRA contribution basis tracking; U.S. Department of Labor, Prohibited Transaction Exemption 2020-02, rollover recommendation documentation requirements, at dol.gov.

Disclaimer: This article is for general information only and is not tax or financial advice. “Wanda Kessler” is a composite character with invented finances, not a real person. 2026 limits shown; confirm current-year eligibility and consult a qualified professional.